Thumbnails not opening

The thumbnails on the product pages don’t load the full image, when clicked they just show a loading animation. I’m not a developer so not sure where to look or how to fix this.

Here’s an example of the problem, http://peanutgallery.co.za/products-page/bedrooms/protect-a-bed/

Any help is appreciated.

https://wordpress.org/plugins/wp-e-commerce/